Structural and crystal-chemical characteristics of the apatite deposits from human aortic walls.

Thermal behavior of biological apatite is the object of several studies. Crystal size, carbonate content, phase composition, and other parameters change during annealing up to 900 °C in biological minerals with apatite structure. The way these parameters change reflects the specific properties of the initial bioapatite. This work presents data on thermal transformations of pathological bioapatite from the human cardiovascular system, namely aortic wall deposits. Some minor elements, foreign to calcium hydroxyapatite (e.g., Na and Mg), can be both incorporated in the apatite structure and localized in the surface layers of crystals, modifying functions of the mineral. A new approach was proposed to determine the predominant location of minor elements, such as Mg, Na, and K, in the mineral of pathological deposits. Mg and Na in pathological apatite can be in both structurally bound (substituting calcium in lattice) and labile (localized on the crystal surface) states, while K is not able to join the apatite structure in significant amount or be chemically bound to it. This approach, based on atomic spectrometry, can be used effectively in combination with a set of traditional techniques, such as like EDS, IRS, and XRD.

Two vicious circles contributing to a diagnostic delay for tuberculosis patients in Arkhangelsk.

SETTING: Delay in tuberculosis (TB) diagnosis increases the infectious pool in the community and the risk of development of resistance of mycobacteria, which results in an increased number of deaths. OBJECTIVE: To describe patients' and doctors' perceptions of diagnostic delay in TB patients in the Arkhangelsk region and to develop a substantive model to better understand the mechanisms of how these delays are linked to each other. DESIGN: A grounded theory approach was used to study the phenomenon of diagnostic delay. Patients with TB diagnostic delay and doctors-phthisiatricians were interviewed. RESULTS: A model named 'sickness trajectory in health-seeking behaviour among tuberculosis patients' was developed and included two core categories describing two vicious circles of diagnostic delay in patients with TB: 'limited awareness of the importance to contact the health system' and 'limited resources of the health system' and the categories: 'factors influencing health-seeking behaviour' and 'factors influencing the health system effectiveness'. Men were more likely to report patient delay, while women were more likely to report health system delay. CONCLUSIONS: To involve people in early medical examinations, it is necessary to increase alertness on TB among patients and to improve health systems in the districts.

A comparison between passive and active case finding in TB control in the Arkhangelsk region.

BACKGROUND: In Russia, active case finding (ACF) for certain population groups has been practiced uninterruptedly for many decades, but no studies comparing ACF and passive case finding (PCF) approaches in Russia have been published. OBJECTIVE: The aim of this study was to describe the main differences in symptoms and diagnostic delay between patients who come to TB services through PCF and ACF strategies. METHODS: A cross-sectional study was conducted among 453 new pulmonary tuberculosis (PTB) patients, who met criteria of TB diagnostic delay in Arkhangelsk. RESULTS: ACF patients used self-treatment more often than PCF patients (90.1% vs. 24.6%) and 36.3% of them were alcohol abusers (as opposed to only 26.2% of PCF patients). The median patient delay (PD) in PCF was 4 weeks, IQR (1-8 weeks), and less than 1 week in ACF. Twenty-three per cent of the PCF patients were seen by a medical provider within the first week of their illness onset. CONCLUSION: Patients diagnosed through ACF tended to under-report their TB symptoms and showed low attention to their own health. However, ACF allowed for discovering TB patients earlier than PCF, and this was also the case for alcohol abusing patients. PCF systems should be supplemented with ACF strategies.

Hopelessness as a basis for tuberculosis diagnostic delay in the Arkhangelsk region: a grounded theory study.

BACKGROUND: Data about delayed tuberculosis diagnosis in Northern Russia are scarce yet such knowledge could enhance the care of tuberculosis. The Arkhangelsk region is situated in the north of Russia, where the population is more than one million residents.The aim of the study was to understand factors influencing diagnostic delay among patients with tuberculosis in the Arkhangelsk region and to develop a theoretical model in order to explain diagnostic delay from the patients' perspectives. METHODS: Twenty-three patients who had experienced diagnostic delay of tuberculosis were interviewed in Arkhangelsk. Using a qualitative approach, we conducted focus-group discussions for data gathering using Grounded Theory with the Paradigm Model to analyse the phenomenon of diagnostic delay. RESULTS: The study resulted in a theoretical model of the pathway of delay of tuberculosis diagnosis in the Arkhangelsk region in answer to the question: "Why and how do patients in the Arkhangelsk region delay tuberculosis diagnosis?" The model included categories of causal conditions, context and intervening conditions, action/interaction strategies, and consequences. The causal condition and main concern of the patients was that they were overpowered by hopelessness. Patients blamed policy, the administrative system, and doctors for their unfortunate life circumstances. This was accompanied by avoidance of health care, denial of their own health situations, and self-treatment. Only a deadly threat was a sufficient motivator for some patients to seek medical help. "Being overpowered by hopelessness" was identified as the core category that affected their self-esteem and influenced their entire lives, including family, work and social relations, and appeared even stronger in association with alcohol use. This category reflected the passive position of many patients in this situation, including their feelings of inability to change anything in their lives, to obtain employment, or to qualify for disability benefits. CONCLUSION: The main contributing factor to unsuccessful health-seeking behaviour for patients with tuberculosis was identified as "being overpowered by hopelessness." This should be taken into consideration when creating any preventive programs and diagnostic algorithms aimed at increasing knowledge about TB, improving the health system, decreasing alcohol consumption and reducing the poverty of the people in Arkhangelsk.